ウェイル音声結晶における表面音波のトポロジカル・ネガティブ・リフレクション
Hailong He1, Chunyin Qiu2, Liping Ye1
1Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, China.
Nature
|August 3, 2018
まとめ
研究者は,ウェイル音声結晶におけるトポロジカルな表面波の負の折れを示している. この音響メタマテリアルは 新しい波の操作を可能にし,高度なデバイスのアプリケーションで 望ましくない反射を防ぐことができます.
科学分野:
- 音響学と材料科学
- 凝縮物質物理学
背景:
- 波の反射や折射のような波現象は 光学レンズなどの波構成要素の製造に不可欠です
- 陽光折射は,伝達された波をインターフェースの正反対側に導きますが,負光折射は,同じ側に導きます.
- 人工材料で観察される負の屈折は,超高解像度画像に潜在的応用がありますが,反射はしばしば避けられない問題です.
研究 の 目的:
- トポロジカルな表面波の負折れを報告する.
- 陰性折射過程における反射の防止を調査する.
- トポロジカル・アコースティック・メタマテリアルを用いた波機能装置の設計を研究する.
主な方法:
- ウェイル半金属の音響類であるウェイル音響結晶を用いた.
- エンジニアリングインターフェイスは,結晶の側面を分離する一次元エッジです.
- 表面の終端を調整して,表面の音波の恒常周波数線を制御する.
主要な成果:
- 特定の結晶界面でのトポロジカルな表面波の負折れが実証された.
- 同じウェイル音晶のサンプル内の異なるインターフェイスで正反射を達成した.
- トポロジカルに保護された表面状態のオープンな恒定周波数の輪郭により,望ましくない波反射を成功裏に防止しました.
結論:
- ウェイル音声晶は,負折射を示すトポロジカルな表面波を宿すことができる.
- ウェイル結晶のユニークな性質は,波の伝播における反射を排除することを可能にします.
- この研究により 先進的な波の機能装置を設計し 波の振る舞いに前例のない制御が可能になりました
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